Doctor for paper-making machines



Dec 30, 1930. J. WENZEL DOCTOR FOR PAPER MAKING MACHINES Filed Nov. l1,'1929 Patented Dec. 39, 1930 UNETEE) STATES JOHN WENZEL, F CHILLIGOTHE,OHIO DOCTOR FOR PAPER-MAKING MACHINES Application filed November 11,1929. Serial No. 406,275.

My invention relates to new and useful improvements in a doctor forpaper making machinery, such as are used for keeping the roll to whichit is applied clean and also preventing paper when it accidentallybreaks from traveling all the way around the roll and has for one of itsobjects to provide a simple and improved means for keeping the doctorblade firmly against the roll to which it is applied.

Another object of the invention is to provide a compact device of thiskind which will be relatively inexpensive in the cost of manufacturealthough strong and durable and efficient in operation.

A further object of the invention is to provide means for readilyadjusting the tension of the doctor blade on the roll to which it isapplied.

A still further object of my invention is to provide a doctor for papermaking machinery consisting of a doctor lever, a handle, an adjustableconnecting rod connected with the lever and handle in such manner thatthe i movement of the handle to either side of the dead center betweensaid handle and the connecting rod will apply the doctor to the roll orremove it therefrom and hold it in either the operative or inoperativeposition according as to which side of the dead center the handle maybe.

WVith these ends in view, this invention consists in the details ofconstruction and combination of elements hereinafter set forth and thenspecifically designated by the claims.

In order that those skilled in the art to which this inventionappertains may understand how to make and use the same, I will describeits constriction in detail, referring by numerals to the accompanyingdrawings forming a part of this application, in which Fig. 1, is an endview of a portion of a paper making machine showing a conductor constructed in accordance with my invention applied thereto and with thedoctor in an inoperative position or applied to the roll.

Fig. 2, is a similar view showing the parts in inoperative positions,the supports for the different parts being eliminated.

Fig. 3, is an edge view of Fig. 2 looking in the direction of'the arrowadjacent said Fig. 2 and in a fragmentary manner illustrating some ofthe connections.

In carrying out my invention as herein embodied, 5 represents the frameof a paper making machine having a roll 6 suitably journalled therein inany usual or well known manner and in the present instance my inven tionis shown in connection with this roll and the machine frame, it beingunderstood that it is desirable to keep said roll in a clean conditionand prevent a broken. strip of paper from running all the way around orwinding the same thereon.

Preferably, Ijsecure brackets 7 to the machine frame in which isjournalled a shaft 8 carryingthe doctor 9 which includes the doctorframe 10 and the doctor blade 11, the latter being flexible and undernormal conditions is adapted to bear against the periphery of the roll6.

On one end of the shaft is mounted the lever 12 by means of the boss 13and said lever is held in any angular adjustment relative to the doctorby means of set screws it.

On some suitable part of the machine frame or on a separate support 15mounted on said machine frame is pivoted one end of the handle 16 as at1'? and at the outer or free end of the handle is a knob or hand held 18for manipulation of the handle.

Intermediate the ends of the handle is pivoted as at 19 one end of anadjustable connecting rod or turn buckle 20 while the other end thereofis pivoted as at 21 to the outer or free end of the lever 12. It is tobe understood that the rod portion designated by the numeral 22 hasright and left hand threads at opposite ends which have threadedengagement with the sockets of the clevises 23. The handle 16 carries astop pin 24 between the axis of the handle and the pivot point of theconnecting rod or turn buckle on said handle and to one side of thelongitudinal center of said handle as plainly shown in Fig. 2.

In practice, when the doctor is in an inoperative position as shown inFig. 1, the handle is to the left of the dead center or imaginary linesimultaneously passing throughthe longitudinal centers of the con- "saryto release or move the doctor from the roll, the handle 16 moved only ashort rlistanceuntil it passes to the right of the:

dead center when the weight of the doctor will quickly move the partsinto an inoperative position as shown in 2.

By rotating the. rod proper 22 of the adjustable connecting rod or turnbuckle through the medium of the polygonal portion 25, the distancebetween the ends of said connecting rod'will be changed or regulated andthus the tension :of the doctor blade 11 against the roll 6 'may beregulated or adjusted. After the proper adjustment has 7 been obtained.the rod proper 22' is held by means of the iock nuts 26. n 7

Of course I do not wish to be limited to the exact details ofconstruction as herein shown, as these may be varied within the limitsof the appended claims without departing from the spirit of myinvention. 77

Having thus fully described my invention, Eililt I claim as new anduseful is 1. A doctor for'paper making machines ineluding a;shaft, adoctor thereon, a lever connected to one end of said shaft, a handlepivot-ed at one end, an adjustable connecting rod having one end pivotedto the handle intermediate the ends of the latter and the other endpivoted to the lever and a stop pin on the handle to one side of thelongitudinal center thereof and between its pivot point and the pivotalconnection of the connecing rod with said handle. 7

2. The structure set forth in claim 1 wherein the adjustableconnecting'rod includes a rod proper having right and left hand threadsat opposite ends and a polygonal portion intermediate the threadedparts, clevises having threaded connection with the rod proper and locknuts on thethreaded partsof said rod proper. 7 T V 3. The combinationwith brackets, a doctor shaft journalled in said brackets, a doctorframe on said shaft and a resilient doctor blade carried by the frame,of a lever for mounting upon said shaft, set screws carried by the leverto hold the same in different adjusted positions on the shaft, a supportfor connection with a machine frame, a handle pivoted at one end to saidsupport, a knob at the opposite end of said handle, an adjustableconnecting rodjn the form of a turn buckle having one end pivoted to thelever and the other endto the handle intermediate its ends whereby whensaid handle and the connecting rod are parallel, the adjacent pivotedends will overlap and said position will be known as the dead center,the device being in an inoperative position when the knob is to one sideof the dead center and with engagement with the adjustable connectingrod and in operative position when the knob is to the other side of thedead center and a stop pin carried by the handle for engagement with theadjustable connecting rod when the device is in operative position.

In testimony whereof, I have hereunto affixed my signature.

J OHN W'EKZEL.

